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National Immunization Provider Record Check Study

The National Center for Health Statistics and the National Immunization Program of the Centers for Disease Control and Prevention implemented the National Health Interview Survey/National Immunization Provider Record Check Study (NHIS/NIPRCS) in 1994 to determine the accuracy of the household vaccination reports for children 12-35 months of age. The purpose of the NIPRCS was to validate the children's immunization histories reported in the NHIS Immunization Supplement against the records obtained from the immunization providers for these children.

NHIS households with children between the ages of 12 and 35 months who completed the Immunization Supplement were asked for permission to contact the children’s immunization providers. The immunization records for each child with permission were requested from the providers. The combined reports from households and providers formed the basis for estimates of vaccination coverage. When the household and provider reports did not agree, a process of reconciliation attempted to resolve any discrepancies. A further step determined best values for the children’s immunization dates. National estimates of vaccination coverage were calculated from these data.

The NHIS/NIPRCS data files contain data from two sources: the National Health Interview Survey Immunization Supplement (NHIS/IM) and the Immunization History Questionnaires (IHQ) completed by the medical providers of children for whom immunizations were reported in the NHIS/IM.